The "accelarated test" may not be in any way indicative of true lifetime in moderate conditions. Their own conclusion does not draw any such implications, the o

The "accelarated test" may not be in any way indicative of true lifetime in moderate conditions. Their own conclusion does not draw any such implications, the only other test they reference is done at 80°C (10°C lower), and the only writing on how or why this test could be indicative of archival lifetime was a generic two sentence: harsher conditions -> faster degradation (in part 4). It was a pupose-built test to see how much of X would Syylex take. It took X better than others, none of which took X well. Tests like these are very good, if you want to go with Syylex, to make sure it's not worse in some way (X, or Y, Z), which would then suggest a need for further examination. In real aging, factor X may be completely meaningless, while Y and Z are crucial, so you cannot conclude which one will last more. Why test 90°C and 85% RH, not 80°C, 50°C or 110°C, or bending, UV light, scratching, drop in acid .. whatever? For a proper accelerated lifetime test, you would need to identify (all) relevant degradation modes and model their behaviour (and interaction) in target vs. accelarated test conditions, and then extrapolate behaviour in target conditions. They didn't even write what type of degradation they are testing.